Mariah & Nick's Island Wedding

They hadn't even gone public with their relationship – in fact, they had only recently begun seeing each other – when Mariah Carey and Nick Cannon decided to take the plunge. "We got tattoos!" says Carey. "His is on one shoulder to the other and it says 'Mariah.'" And hers? "It's on my lower back and it says 'Mrs. Cannon,'" she says. Only after that did they ink a marriage license – and pull off the surprise wedding of the year. Carey and singer-actor Cannon first met in 2005 at the Teen Choice Awards but only started dating in late March. Just weeks later, to the shock of a lot of their friends and family, they whisked off to Carey's Bahamian estate and wed in a sunset, ocean-side ceremony April 30. While still on their honeymoon, the giddy newlyweds spoke exclusively to PEOPLE's Liz McNeil about their whirlwind courtship, Cannon's candy-themed proposal and – yep – having kids.

So, how does it feel to be married?Mariah: [Laughing] Who wants to go first? You go first.

Nick: It feels amazing. My cheeks hurt from smiling so hard. I've been smiling for days.

Mariah: It's comforting – and something I've never felt before. Which is really being in love and happy with someone who really understands me and isn't trying to do anything but make me happy. It's wonderful.

It happened pretty fast, didn't it?Nick: In our minds, it was a love-at-first-sight thing. Since we've been together, we've been inseparable.

Mariah: I don't think anyone realized what we already knew – that we were going to get married.

When did you first know that?Nick: I'd always admired Mariah from afar, but once we connected I felt it was destined: This has to be my wife.

Mariah: I definitely knew. Of course, everyone is running the photo from the 2005 Teen Choice Awards . . .

Nick: From then on, I thought, "I have to get closer to her and express my true feelings." I was praying I'd have the chance to share them with her.

Mariah: People were very skeptical and told him, "You can never get past her people." I only knew that he'd say nice things about me. So I thanked him when [I saw him again].

Nick: I said, "I meant every single word. Hopefully I can express more to you." She was down-to-earth. From that point, we built a friendship.

In late March, Carey flew to Antigua to shoot a music video for "Bye Bye," from her new album, E=MC2. She cast Cannon, 27 – star of MTV's Wild'N Out, and an entertainment minimogul with his own record label and clothing line – as the romantic lead.

Mariah: I told people, "I like him and want him to do it." The song was a love story. It was perfect for us.